1. Field of the Invention
The present invention relates to a divided type rolling bearing unit of such a type that a raceway is divided along a shaft center.
2. Description of the Related Art
In this type of divided type rolling bearing unit, each of components such as an inner ring, an outer ring, and a bearing housing is divided into two parts along a shaft center such that it is easily attachable to or detachable from a shaft member or a neck portion of a roll.
In order to assemble the bearing in a guide roll or the like of continuous casting facilities of an iron mill, for example, which is the shaft member, the lower half of each of the divided components is assembled in the roll, the upper half of the component is then assembled, and the upper half and the lower half are integrated upon being tightened by a bolt.
When a high load at the time of casting is applied, the guide roll is deflected downward. Further, at the time of mounting the roll, a shaft center of the bearing integrally assembled may, in some cases, be shifted by a very small amount in a direction in which castings are fed (in the horizontal direction in this case). In such a case, the aligning characteristics of the bearing are important so as not to exert an excessive force on the bearing.
Conventionally in this type of divided type aligning rolling bearing unit, the outer ring is constituted by a semicircular upper member and a semicircular lower member, and the outer ring upper member is also used as an upper housing of the bearing housing. The outer ring lower member which receives a load is supported by a lower housing of the bearing housing. The outer ring lower member has its outer peripheral surface formed in a spherical shape in order to obtain an automatic aligning function. In order to regulate the aligning range of the outer ring lower member, both ends in the axial direction of the lower housing which receives the outer ring lower member are provided with ribs, and the ribs are used as stoppers upon being abutted against both end surfaces of the outer ring lower member.
If the ribs for regulating the aligning range thus exist on both sides of the outer ring lower member, a lower housing 91 must be rotated in its circumferential direction when an outer ring lower member 90 is detached from the lower housing 91 for the purpose of maintenance, as shown in FIG. 8. In this case, the posture of the outer ring lower member 90 is unstable because the outer ring lower member is likely to slide, so that work is very difficult.